How to declare “throws” for `subscript(dynamicMember:)`in @dynamicMemberLookup in swift?
When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
asked Nov 15 '18 at 17:53
leavezleavez
94621123
add a comment |
When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
asked Nov 15 '18 at 17:53
leavezleavez
94621123
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 '18 at 18:02
add a comment |
When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
asked Nov 15 '18 at 17:53
leavezleavez
94621123
When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
swift subscript throws
asked Nov 15 '18 at 17:53
leavezleavez
94621123
asked Nov 15 '18 at 17:53
leavezleavez
94621123
asked Nov 15 '18 at 17:53
leavezleavez
94621123
asked Nov 15 '18 at 17:53
leavezleavez
94621123
asked Nov 15 '18 at 17:53
leavezleavez
94621123
94621123
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 '18 at 18:02
add a comment |
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 '18 at 18:02
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 '18 at 18:02
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 '18 at 18:02
add a comment |
1 Answer
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active
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votes
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 '18 at 18:06
leavezleavez
94621123
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 '18 at 18:06
leavezleavez
94621123
add a comment |
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 '18 at 18:06
leavezleavez
94621123
add a comment |
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 '18 at 18:06
leavezleavez
94621123
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A
public subscript(dynamicMember member: String) -> () throws -> Any
return try REAL_FUNCTION_THAT_THROWS()
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 '18 at 18:06
leavezleavez
94621123
answered Nov 15 '18 at 18:06
leavezleavez
94621123
answered Nov 15 '18 at 18:06
leavezleavez
94621123
answered Nov 15 '18 at 18:06
leavezleavez
94621123
94621123
add a comment |
add a comment |
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Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 '18 at 18:02